In RefactoringImprovingTheDesignOfExistingCode, MartinFowler recommends something like this:
If you get in the habit of noticing what classes have what responsibilities, you'll often come across cases where this seems to be your only choice. For example, when dealing with a library beyond your control.
MartinFowler goes on to recommend:
[My copy of _Refactoring_ isn't handy -- can someone please double-check this stuff for me?]